Previous apparatus to make "microwave coffee" either use the percolation method (U.S. Pat. No. 4,642,443) or control the deposit of heated water onto the coffee grounds by a temperature sensitive valve (U.S. Pat. Nos. 4,104,957, 4,381,696 and 4,132,039). The valve in these type microwave coffee makers is adapted to open at a predetermined temperature of the water retained in a reservoir. Upon opening of the valve, the entire quantity of water retained in the reservoir is deposited onto the coffee grounds.
Previous coffee brewing apparatus, which operate outside of a microwave oven, have been known to brew coffee using a water transfer method that relies on a pressure increase created within a sealed vessel during the water heating process (U.S. Pat. No. 4,200,039).